The invention relates to a method, to a computer program and to a computer-readable medium for controlling a pressure in an injection system for an engine of a vehicle.
In order to save fuel, vehicles can be equipped with an “automatic start/stop system”, which automatically switches off the engine of the vehicle when the vehicle is stationary and restarts it automatically for driving onward.
On vehicles with high pressure injection systems, such as diesel vehicles, it may be advantageous if the pressure in the injection system is below an idling pressure (e.g. approximately 500 bar) when starting the engine in order, for example, to ensure a defined and thermodynamically optimum engine start. For this purpose, the residual pressure remaining in the injection system can be deliberately reduced further during the engine stoppage (e.g. to approximately 300 bar).
Particularly for commercial vehicles, injection systems or the injection system are generally designed for emergency running. That is to say, they have installed pressure control valves which ensure a certain minimum injection pressure (e.g. approximately 900 bar), thus allowing continued operation of the vehicle in the event of faults. This pressure is normally above the idling pressure, making it necessary to reduce the injection pressure to attain the idling pressure, e.g. by means of the injections themselves.